Congrats on finishing the Nathans!
I recently finished all the tweaks and mods to my Horn Shoppe Horns and hope to post some pics soon. They're sounding really, really good too.
I bought the Horns with no finish, just bare wood and some tan color faux stone applied to the Horn mouth, and then did the following:
1.) Had a local audio buddy/ pro cabinetmaker veneer and lacquer all sides but the horn mouth with Aussie Lacewood with a light tint of red analine dye.
2). Re-orient the drivers to the square orientation instead of the original diamond configuration and install #8 threaded brass inserts.
3) drill flush hole for ballast fill port cover plate and then 1/2" hole in the center of that for filling BBs.
4) replaced stock binding posts with solid, unplated copper CMC posts and rewired with a 16" length of Chimera Labs 7-7 enameled OCC Litz wire.
5) applied 1/8" industrial noise absorbtion grade felt to upper and lower horn mouths, and rear, and back 4" of compression chamber left, right, and top surfaces.
6) Applied 3/16" gore-tex gasket around driver opening, soldered Planet 10 modified FE-126s in place (with the fluffy wool pad glued on the back of the magnet), and bolted drivers in place with #8 brass button head machine screws.
7) Filled bottoms of speakers with 24,000 BBs per side, stuffed remaining empty space with wads of compressed heavy craft paper, and screwed aluminum cover plates in place.
Setup, connect speaer wires, and enjoy...
Will post pics soon as I can figure out how to shrink them.